Apparatus for forming curved, rectangular bodied needle blanks from tubular stock

ABSTRACT

There is disclosed an apparatus for forming curved and rectangular bodied needle blanks from a length of needle stock which includes a generally cylindrical inner mandrel having a plurality of longitudinal channels formed in an outer surface thereof, the mandrel being dimensioned and configured for insertion within the length of needle stock. The apparatus also includes a plurality of broaches insertable into the longitudinal channels such that an edge of each broach projects radially outwardly of the mandrel to form a plurality of inner grooves on an inner surface of the length of needle stock. There is also provided structure for forming outer grooves in an outer surface of the length of the needle stock to form a substantially grooved length of needle stock, cutters for cutting the grooved length of needle stock to form rings of curved rectangular bodied needle blanks interconnected by web portions and structure for dividing the rings at the web portions to form a plurality of curved rectangular bodied needle blanks. There is also disclosed a method of forming needle blanks from a length of needle stock having a longitudinal cavity therethrough and defining a longitudinal axis by forming at least two inner grooves in an inner surface of the length of needle stock and substantially parallel to the longitudinal axis, forming a number of outer grooves, equal to the number of inner grooves, in an outer surface of the length of needle stock and in substantial radial alignment with the at least two inner grooves to form a grooved length of needle stock and sectioning the grooved length of needle stock to form individual needle blanks.

This is a divisional of U.S. application Ser. No. 08/590,226 filed Jan.23, 1996, now U.S. Pat. No. 5,682,940.

BACKGROUND

1. Technical Field

The technical field relates generally to the formation of surgicalneedle blanks, and more particularly, to apparatus for forming needleblanks and methods of forming curved and rectangular bodied needleblanks from a ring, or length of needle stock formed to produce a ring.

2. Description of Related Art

The production of needles involves many processes and different types ofmachinery in order to prepare quality needles from raw stock. Thesevarying processes and machinery become more critical in the preparationof surgical grade needles where the environment of intended use is inhumans or animals. Some of the processes involved in the production ofsurgical grade needles include, inter alia, straightening wire stockfrom a reservoir, cutting needle blanks from wire stock, tapering orgrinding points on one or both ends of the blank, and providingstructure for receiving a suture thread at an end of the blank or at alocation intermediate the ends. As used herein, the term "needle blank"refers to a piece of needle stock at various stages of completion butnot fully formed into a surgical grade needle suitable for use duringsurgical procedures. Additionally, one skilled in the art willappreciate that flat surfaces may be formed on sides of the blank,typically by flat pressing portions of the needle blank to facilitategrasping by surgical instrumentation. Curving of the needle blank mayalso be performed where curved needles are desired. When providingcurved and flat side or rectangular bodied needles for surgicalprocedures it is desirable for the needles to have a specifiedrectangular cross-section and a specified curvature, i.e., apredetermined radius of curvature. The desired cross-section and radiusof curvature for the finished needle varies with specific applications.

When forming flat sided or rectangular bodied needle blanks, the needleblank material is compressed and deformed during the pressing operationthereby raising the potential for creating unwanted stresses in theneedle blank. Further, when surgical grade needles are made of steel orsimilar resilient materials, the curving anvil or mandrel used must havea smaller radius than the desired radius of the final surgical needle.This configuration compensates for a "springback" or radial expansioneffect after the curving operation to ensure that the desired radius ofcurvature is attained.

Certain types of surgical grade needles, such as, for example, doublepointed and curved needles, or surgical incision members, typicallyrequire several processes to form the finished product. These processesmay include curving and cutting needle stock to form needle blanks,altering or refining the tip configurations and curvature radius,punching or drilling the blank to form a suture hole and/or notching theblank to provide engaging structure for cooperative instrumentation.

Conventional needle processing is, in large part, a labor intensiveoperation requiring highly skilled labor. One disadvantage toconventional needle processing is that most needle processingoperations, such as, for example, cutting the blanks from stock,tapering the stock to form points, flat and side pressing of the bodyportion of the blanks, curving the blanks, etc., must be performed onseparate processing machines.

Thus it would be desirable to have an apparatus for forming a largenumber of curved and rectangular bodied needle blanks, suitable forfurther finishing and refining, in a very short time and with a minimalamount of machinery. It would further be desirable to have an apparatusand a method of forming curved needle blanks having a desired radius ofcurvature without having to compensate for springback or otheralterations of curvature radius. It would be still further desirable tohave an apparatus and a method of forming flat sided or rectangularbodied needle blanks without having to press or compress the needleblank material.

SUMMARY

The disclosed surgical instrumentation relates to apparatus for formingneedle blanks from a ring of needle stock or, alternatively, a length ofmaterial manipulated to form such a ring. Broadly stated, the apparatusgenerally includes supporting structure for supporting the ring ofneedle stock and machining structure for imparting a plurality of needleblank shapes in the ring of needle stock. In one embodiment, theapparatus includes an inner mandrel having at least one broach receivingchannel formed in an outer surface thereof and being dimensioned andconfigured to fit within the ring of needle stock. At least one broachis provided and is configured for slidable insertion within the broachreceiving channel such that at least a portion of the broach projectsbeyond the outer surface of the mandrel. When positioned within thechannel, the projecting portion of the broach forms grooves in an innersurface of the ring of needle stock surrounding the mandrel. Theapparatus further includes structure for forming grooves on an outersurface of the ring of needle stock in substantial radial alignment withthe grooves in the inner surface of the ring of needle stock, andcutters for cutting the grooved ring of needle stock to form individualneedle blanks.

The inner mandrel is preferably configured and dimensioned to fit theshape defined by the inner circumferential surface of the ring of needlestock. The broach preferably has a leading cutting edge and at least onetapered side edge. The apparatus may further include driving structureto drive the broaches within the channels.

There is also disclosed a method of forming a needle blank from a ringof needle stock by mechanically imparting a plurality of needle blankshapes into the material of the ring of needle stock.

Preferably, this is accomplished by forming at least two inner groovesin an inner surface of the ring of needle stock and substantiallyparallel to a longitudinal axis thereof and forming a number of outergrooves, equal to the number of inner grooves, in an outer surface ofthe ring of needle stock and in substantial radial alignment with the atleast two inner grooves to form a grooved ring of needle stock.Thereafter, the grooved ring of needle stock is sectioned to formindividual needle blanks. The step of sectioning preferably includescutting the grooved ring of needle stock substantially perpendicular tothe longitudinal axis to form at least one ring of needle blanksinterconnected by web portions defined by the inner and outer grooves,and severing the web portions to divide the ring into individual needleblanks.

In accordance with another embodiment, an apparatus for forming a ringof curved rectangular bodied needle blanks from a ring of needle stockis provided which includes a fixture to hold the ring of needle stockand a die having a pair of concentric cutting edges projectingtherefrom. Each cutting edge of the die is dimensioned and configured toimpart a series of alternating flat sided cuts to the ring of needlestock. Preferably, each of the concentric cutting edges alternatesbetween arcuate segments of greater radius and arcuate segments oflesser radius such that the arcuate segments of greater radius of one ofthe pair of concentric cutting edges is in substantial radial alignmentwith the arcuate segments of lesser radius of the other concentriccutting edge.

BRIEF DESCRIPTION OF THE DRAWINGS

Various embodiments are described herein with reference to the drawings,wherein:

FIG. 1 is a perspective view of an apparatus for forming curvedrectangular bodied needle blanks from a length of needle stock withparts separated;

FIG. 2 is an assembled perspective view, partially in section, of theapparatus of FIG. 1;

FIG. 3 is a partial cross-sectional view of the apparatus of FIG. 1depicting a broach being forced between an inner mandrel and the lengthof needle stock;

FIG. 3a is cross-sectional view of a broach taken along line 3a--3a ofFIG. 3;

FIG. 3b is a cross-sectional view taken along line 3b--3b of FIG. 3;

FIG. 4 is a perspective view of the length of needle stock, grooved oninner and outer surfaces thereof, and sliced to form a ring of curvedrectangular bodied needle blanks;

FIG. 4A is a perspective view of the length of needle stock illustratingan alternate method of forming grooves in an outer surface thereof;

FIG. 5 is a perspective view of the grooved ring of needle stocksectioned to form curved, rectangular bodied needle blanks;

FIG. 6 is a perspective view of a curved, rectangular bodied needleblank formed by the apparatus of FIG. 1;

FIG. 6A is a side elevational view of a die for forming apparatusengagement notches in the needle blank of FIG. 6;

FIG. 6B is an end view of the die face of FIG. 6A.

FIG. 7 is a side elevational view of an alternate embodiment of anapparatus for forming a ring of curved, rectangular bodied needleblanks;

FIG. 8 is a perspective view of holding fixture holding a ring of needlestock;

FIG. 9 is an perspective view of a needle blank ring cut from flatneedle stock;

FIG. 10 is an end view taken along the line 10--10 of FIG. 7 showing thecutting die face of the apparatus of FIG. 7;

FIG. 11 is an end view of an alternate cutting die face for formingstraight, rectangular bodied needle blanks; and

FIG. 12 is a perspective view of a straight, rectangular bodied needleblank.

DESCRIPTION OF PREFERRED EMBODIMENTS

The preferred embodiments illustrated and discussed herein are directedto the ultimate formation of a surgical incision member for use inremote suturing in a body cavity. It is contemplated that theillustrated structure and methods can easily be used in the formation ofany needle configuration including single pointed needles, of varyingcross-sectional shapes, straight needles, etc.

Referring now to FIG. 1, an apparatus 10 is illustrated which isparticularly suited to form a series of longitudinal cuts in a tube orring of needle stock such as, for example, length of tubular needlestock 12, in order to partially form a number of curved and pre-pointedneedle blanks therein. Apparatus 10 generally includes support structurefor supporting a ring of needle stock 12. In this embodiment the supportstructure includes an inner mandrel 14 which is insertable withintubular needle stock 12. Means for imparting a plurality of needle blankshapes is also provided. In this embodiment, the means for imparting aplurality of needle blank shapes includes at least one cutting die orbroach 16 which, when forced between inner mandrel 14 and tubular needlestock 12, imparts a longitudinal groove in tubular needle stock 12.Apparatus 10 additionally includes a driver 18 which is configured fordriving broach 16 between inner mandrel 14 and length tubular needlestock 12.

Preferably, tubular needle stock 12 consists of tubular shapedbicompatable material of the type suitable for forming surgical gradeneedles such as, for example, stainless steel, etc. Preferably, tubularneedle stock 12 has a wall thickness selected generally to conform tothe thickness of a finished surgical needle. In order to form tubularneedle stock 12 into surgical needle blanks it is desirable to impart aseries of longitudinal grooves along both an outer surface 20 and aninner surface 22 of tubular needle stock 12. The longitudinal groovesalong inner surface 22 of tubular needle stock 12 are formed usingbroaches 16, preferably formed with a leading cutting edge 24 and sidecutting edges 26. When these cutting edges 24, 26 are forced betweeninner mandrel 14 and inner surface 22 of tubular needle stock 12, alongitudinal three sided groove 34 is formed within inner surface 22(FIG. 4).

Inner mandrel 14 is preferably dimensioned and configured to fit closelywithin tubular needle stock 12. Inner mandrel 14 is provided with amounting portion 28 for attachment to an external holding fixture 17,(see FIG. 2) and a broach retaining portion 30 configured to guidebroaches 16 between inner mandrel 14 and inner surface 22 of tubularneedle stock 12. Mounting portion 28 is configured to be held by theexternal holding fixture such that inner mandrel 14 does not move asbroaches 16 are driven therealong. Preferably broach retaining portion30 includes plurality of circumferentially spaced and longitudinallyextending channels 32 which are adapted to receive broaches 16. Whenbroaches 16 are inserted within channels 32, cutting edges 24 and 26project from an outer surface of die retaining portion 30 to engageinner surface 22 of tubular needle stock 12. In this manner, as broaches16 are moved by driver 18 within channels 32, cutting edges 24 and 26projecting from mandrel 14 cut or score longitudinal grooves withininner surface 22 of tubular needle stock 12.

Referring now to FIGS. 2 and 3, in operation, inner mandrel 14 isinitially positioned coaxially within tubular needle stock 12 andmounting portion 28 is mounted within a holding fixture 17. Broaches 16,which are mounted to driver 18, are inserted within channels 32 andforced longitudinally within channels 32 by driver 18 in order to scoreor cut grooves into inner surface 22 of tubular needle stock 12.Referring specifically to FIGS. 3, 3a and 3b, as broaches 16 are drivenwithin channels 32, base portions 27 of broaches 16 ride within channels32 while leading cutting and side edges 24 and 26, respectively, engageinner surface 22 of tubular needle stock 12 to progressively cut threesided grooves 34 within inner surface 22.

During broaching of inner surface 22 of tubular needle stock 12, it ispreferable to securely hold tubular needle stock 12 against relativemovement with respect to inner mandrel 14. Various non-destructive ornon-marring methods, such as, for example, padded clamping etc. may beused to hold tubular needle stock 12 stationary with respect to innermandrel 14 during the broaching operation.

Referring now to FIG. 4, after broaching, tubular needle stock 12 has aplurality of circumferentially spaced and longitudinally extendinggrooves 34 formed in inner surface 22. In order to form a plurality ofinterconnected needle blanks from tubular needle stock 12, means forforming grooves on an outer surface of the needle stock material areprovided, in this embodiment, a grinder 38 is provided as the means forforming grooves on the outer surface. It is preferable to form an equalnumber of corresponding and longitudinally extending external grooves 36in outer surface 20 of tubular needle stock 12 corresponding to thegrooves 34 formed in the inner surface. Grinder 38 includes a grindingwheel 40 which is movable toward and away from tubular needle stock 12and, more importantly, moveable longitudinally with respect to tubularneedle stock 12 in order to impart grooves 36 corresponding to grooves34. Although shown here with a movable grinder 38, one skilled in theart will readily appreciate that a fixed grinder could be used and theneedle stock material moved relative thereto.

Grinding wheel 40 can have any desired configuration depending upon theshape of the groove to be formed. Preferably, grinding wheel 40 includesa flush bottom cutting surface 42 and an angled side cutting surface 44such that when grinder wheel is engaged and moved longitudinally alongouter surface 20 it imparts a three sided groove 36 substantiallysimilar to inner three sided grooves 34. Preferably, grooves 36 areformed in outer surface 36 in substantial radial alignment with innergrooves 34 formed in inner surface 22, that is, along the same radiallines, to define a series of needle blank segments and connected by webportions as more fully described hereinbelow.

Alternatively, it may be preferable to broach or cut grooves 36 intoouter surface 20 in a manner substantially similar to the broaching ofinner grooves 34. Referring to FIG. 4A, an outer member 46 is providedhaving a longitudinal channel 48 therein. Outer member 46 is configuredto conform to the shape of the needle stock material around which it ispositioned. In this embodiment, outer member 46 is formed as a cylinderinto which tubular needle stock 12 is inserted. A broach 50, similar tobroach 16, is longitudinally inserted within channel 38 and engagessurface 20 of tubular needle stock 12 separately from, or optionallysimultaneously with, the broaching of inner surface 22. Other apparatusor methods of forming grooves 36 in outer surface 20 are alsocontemplated and include providing structure for stamping die 50 intoouter surface 20 in order to stamp grooves 36 into outer surface 20, aswell as chemical or electrochemical etching., etc.

Referring back to FIG. 4, once grooves 34 and 36 have been formed withininner and outer surfaces 22 and 20 in tubular needle stock 12,respectively, grooved tubular needle stock 12 may be sectioned to formindividual needle blanks. Tubular needle stock 12 is initially slicedperpendicular to its longitudinal axis to form rings 52, each containinga plurality of needle blanks 54 interconnected by web portions 56.Various methods may be used to slice or cut grooved tubular needle stock12 into rings 52, such as, for example, by cutting with a saw type bladeor with a laser cutter. Additionally stamping or grinding operationsutilizing flat cutting action may be performed perpendicular to thelongitudinal axis of grooved tubular needle stock 12 to form rings 52.Rings 52 are formed with a thickness corresponding to the desired needlethickness. Preferably, rings 52 are on the order of approximately 0.03to 0.05 inches thick and, more preferably, approximately 0.034 inchesthick. As used herein, the above described methods are means for cuttinggrooved tubular needle stock 12 substantially perpendicular to itslongitudinal axis.

Rings 52 also may be formed by various methods or dies which impart around rather than rectangular configuration to the ring 52 of needleblanks to ultimately form curved round-bodied needles rather than curvedrectangular bodied needles.

Ring 52 has an inner circumferential surface 58 and an outercircumferential surface 60 which, due to inner and outer grooves 34 and36, respectively, each have segments of alternating radii. For example,ring 52 has an inner radius r1 along that portion of innercircumferential surface 58 which was not broached and corresponds toinner surface 22. Inner circumferential surface 58 has a second radiusr2 at web portions 56 which corresponds to broached channels 34.Similarly, outer circumferential surface 60 has an outer radius r3 whichcorresponds to unbroached outer surface 20 and outer radius r4 whichcorresponds to longitudinally broached channels 36 in outer surface 20.Thus, the inner and outer circumferential surfaces, 58 and 60,respectively, of ring 52 alternate between various segments of greaterand lesser radius to define a plurality of needle blank segments 54interconnected by web portions 56. Depending on the spacings betweenadjacent grooves 34 or 36, needle blanks 54 may have equal or varyingarcuate lengths. At this point, ring 52 may be taken to various otherforming stations to impart various other characteristics to blanks 54,such as, for example, hole drilling, notching, polishing, stamping toform round-bodied needle blanks, etc.

Referring now to FIG. 5, once ring 52 has been formed from groovedtubular needle stock 12, ring 52 may be divided at web portions 56 toform a plurality of individual needle blanks 62. As noted above, needleblanks 62 may have various arcuate lengths according to the distancesbetween adjacent grooves 34, 36 formed in tubular needle stock 12 andpreferably have a length of approximately 0.4 inches.

An individual needle blank 62 for ultimate processing into a surgicalincision member is illustrated in FIG. 6 and generally includes cut webportions 64 formed on end portions 66 which, in conjunction with angledside portions 68, form an initial taper or pre-point at either endportion 66 of needle blank 62.

Needle blank 62 may thereafter be taken to various other apparatus andprocessing stations for subsequent final tapering or pointing, impartingnotches adjacent either end and hole drilling to form a surgicalincision member, and, where round body needles are desired, may bepressed within various apparatus to form curved round bodied needles.Ends 66 may be finished on various taper grinding and pointingmachinery. Referring to FIGS. 6, 6a and 6b, for example, notches 67 maybe formed in needle blank 62 by stamping or coining with a die 69 (FIGS.6A and 6B) having a pair of projecting notching surface 71.

Referring now to FIG. 7 there is disclosed an alternate apparatus forforming a ring of curved and double pre-pointed rectangular-bodiedneedle blanks. Apparatus 70 includes means for imparting a plurality ofneedle blank shapes in a ring of needle stock material. In thisembodiment, cylindrical die 72 serves to impart a plurality of needleblank shapes into ring of needle stock 76. Supporting means forsupporting the ring of needle stock 76 includes fixture 74. Ring ofneedle stock 76 is preferably formed of a biocompatible material similarto tubular needle stock 12.

Referring to FIGS. 7, 9 and 10, die 72 has a die face 78 which includesa pair of concentric cutting edges 80 projecting therefrom. Cuttingedges 80 generally include an outer cutting ring 82 which is used toimpart a series of alternating circumferential segments within ring ofneedle stock 76 having greater and lesser radii r3 and r4, respectively,similar to that described hereinablve with respect to ring 52. Outercutting ring 82 has outer circumferential cutting edges 84 having aradius r3 and outer web cutting edges 86 having a radius r4. Outercircumferential cutting edges 84 and outer web cutting edges 86 areinterconnected by angled cutting edges 88. Similarly, inner cutting ring90 has inner circumferential cutting edges 92 having an inner radius r1and inner web cutting edges 94 having radius r2. Inner circumferentialcutting and inner web cutting edges, 92 and 94, respectively, areinterconnected by angled cutting edges 96. Outer circumferential cuttingedge 84 of outer cutting 92 functions with inner circumferential cuttingedge 92 of inner cutting ring 90 to cut the needle blank segment fromring of needle stock 76. Similarly, outer web cutting edge 86 functionswith inner web cutting edge 94 to cut the web portions of a ring ofneedle blanks from ring of needle stock 76. Angled cutting edges 96serve, along with angled cutting edges 88, to pre-point needle blankscontained within a ring of cut needle material. It will be appreciatedthat cutting edges 80 may be contained in a separate die body 98 whichis removably attached to die 72 in order to vary the radii of thearcuate segments, as well as the lengths of the individual needleblanks, cut within the ring and the angles of the pre-points. Referringto FIG. 8, fixture 74 preferable includes a pair of separable halves 75and 77 each having a semi-circular inner holding portion 79 and 81,respectively. Fixture halves 75 and 77 are connectable to firmly holdring of needle stock 76 between semi-circular inner holding portions 79and 81 during the stamping operation.

In operation, die 72 is forced down against ring of needle stock 76causing cutting edges 80 to cut ring 100 out of ring of needle stock 76.Ring 100 includes a plurality of needle blanks 102 interconnected by webportions 104. Once ring 100 has been cut fixture halves 75 and 77 may beseparated to release ring 100 and ring 100 may be segmented into variousindividual needle segments or blanks similar to needle blanks 62described hereinabove.

Referring now to FIG. 9, a needle blank ring 100 is shown and is similarto needle blank ring 52 described hereinabove. Needle blank ring 100 cansubsequently be taken to various processing stations for segmenting andvarious other operations, such as, hole drilling, notching, taper pointfinishing, etc.

Referring now to FIG. 11, there is disclosed an alternate die 106 forforming a plurality of straight and rectangular bodied needle blanksfrom a rectangular ring or flat sheet of needle stock. Die 106 has apair of inner and outer cutting edges 108 and 110 which, like cuttingedges 82 and 90 described hereinabove, alternate between interconnectedsegments in order to cut a plurality of straight needle blanksinterconnected by web portions from the rectangular ring of needlestock. A straight, pre-pointed and rectangular bodied needle blank 112cut by die 106 is best illustrated in FIG. 11.

It will be understood that various modifications may be made to theembodiments disclosed herein. For example, the inner mandrel may have avariety of shapes, such as, for example, elliptical to form needleblanks of varying radius, or of a rectangular cross-section such thatwhen the inner mandrel is disposed within a rectangular tube of needlestock material the rectangular tube of needle stock material may bebroached, ground or stamped to form a series of interconnected straightrectangular bodied needle blanks which may be subsequentially divided toform a plurality of individual straight and rectangular needle blanks.Therefore, the above description should not be construed as limiting,but merely as exemplifications as preferred embodiments. Those skilledin the art will envision other modifications within the scope and spiritof the claims appended hereto.

What is claimed is:
 1. An apparatus for forming needle blanks from aring of needle stock comprising:a) means for supporting a ring of needlestock; and b) means for imparting a plurality of needle blank shapes inthe ring of needle stock.
 2. The apparatus according to claim 1, whereinthe means for supporting the ring of needle stock includes a mandrelinsertable within the ring of needle stock.
 3. The apparatus accordingto claim 1, wherein the means for supporting the ring of needle stockincludes a fixture for holding the ring of needle stock therein.
 4. Theapparatus according to claim 1, wherein the means for imparting aplurality of needle blank shape in the ring of needle stock includes atleast one broaching die.
 5. The apparatus according to claim 1, whereinthe means for imparting a plurality of needle blank shapes in the ringof needle stock includes a stamping die having concentric cutting edges.6. An apparatus for forming needle blanks from a ring of needle stockcomprising:a) an inner mandrel having at least one broach receivingchannel formed in an outer surface thereof, the mandrel beingdimensioned and configured to support and fit within a ring of needlestock; b) at least one inner broach configured for movement within thebroach receiving channel, at least a portion of the at least one innerbroach projecting beyond the outer surface of the mandrel such that,when moved within the channel, the projecting portion of the at leastone inner broach forms grooves in an inner surface of the ring of needlestock supported by the mandrel; and c) means for forming grooves on anouter surface of the ring of needle stock in substantial radialalignment with the grooves formed in the inner surface of the ring ofneedle stock to form needle blanks of a predefined shape.
 7. Theapparatus according to claim 6, wherein the means for forming grooves inthe outer surface of the ring of needle stock includes a grinder havinga grinding wheel engagable with the outer surface of the ring of needlestock, the grinder being mounted for relative movement with respect tothe ring of needle stock.
 8. The apparatus according to claim 6, whereinthe means for forming grooves in the outer surface of the ring of needlestock includes:a) an outer member positionable against the outer surfaceof the ring of needle stock, the outer member having a broach receivingchannel formed therein; and b) an outer broach slidable within thebroach receiving channel and having an edge that projects beyond theinner surface of the outer member.
 9. The apparatus according to claim 6wherein at least a portion of the at least one inner broach has atrapezoidal cutting leading edge.
 10. The apparatus according to claim 6further comprising means to drive the at least one inner broach withinthe channel.
 11. The apparatus according to claim 6 wherein the at leastone inner broach has a tapered leading edge.
 12. The apparatus accordingto claim 6 wherein the at least one inner broach has at least onetapered side edge.
 13. An apparatus for forming a ring of curvedrectangular bodied needle blanks from a ring of needle stockcomprising:a) a fixture to hold a ring of needle stock; and b) a diehaving a pair of concentric cutting edges projecting therefrom, eachcutting edge dimensioned and configured to impart a series of arcuatecuts to the ring of needle stock.
 14. The apparatus according to claim13 wherein each of the concentric cutting edges alternates betweenarcuate segments of greater radius and arcuate segments of lesser radiussuch that the arcuate segments of greater radius of one of the pair ofconcentric cutting edges is in substantial radial alignment with thearcuate segments of lesser radius of the other concentric cutting edge.15. An apparatus for forming curved rectangular bodied needle blanksfrom a tube of needle stock comprising:a) a generally cylindrical innermandrel having a plurality of longitudinal channels formed in an outersurface thereof, the mandrel being dimensioned and configured forinsertion within a tube of needle stock; b) at least one broach affixedat one end to a driver mechanism and insertable into the longitudinalchannels such that an edge the at least one broach projects radiallyoutwardly of the mandrel to form a plurality of inner grooves on aninner surface of the tube of needle stock when driven thereagainst; c)means for forming outer grooves in an outer surface of the tube ofneedle stock, the outer grooves being in substantially radial alignmentwith the inner grooves to form a substantially grooved tube of needlestock; and d) means for cutting the grooved tube of needle stocksubstantially perpendicular to a longitudinal axis of the grooved tubeof needle stock to form rings of curved rectangular bodied needle blanksinterconnected by web portions.